Preparing nitrogenous compounds.



, L L. SUMMERS. PREPARING NITRQGENOUS GOMPOUNDS. APPLICATION H'Lnn MAYG,1909.'

1 33 42 Patented July 30,1912.

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WI T NESSES:

WOBMZ I 7L; ATTORNEYS L. L. SUMMERS. PREPARING NITROGENOUS COMPOUNDS.

APPLIGATION FILED MAY 6, 1909.

1,083,842., Patented July30,1912.

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WITNESSES IN VEN TQR WM, ATTORNEY:

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err ra FEQ LELAND L. SUMMERS, or CHICAGO, ILLINOIS.

PREPARING NITROGENOUS COMPOUNDS.

Specification of Letters Patent. 9

Patented July30, 1917?;

To all whom it may concern:

Be it known that I, LELAND L. SUMMERS, a citizen of the United States,residing at Chicago, Cook county, Illinois, have invented a new anduseful Process of Preparing Nitrogenous Compounds, of which thefollowing is a specification.

The object of my invention is to provide a new and useful process ofpreparing or forming nitrogenous compounds, such as cyanogen (LN, andammonia NH together with the numerous salts derived from thesecompounds, the nitrogen from the atmosphere being preferably used,though other sources of nitrogen may be utilized, as hereinafter madeapparent. I

Speaking in general terms, my process consists in preparing nitro'genduscompounds by treating a metal nitrid with ammonia and hydrogen in thepresence of heated carbonaceous material and in the practice of myprocess I prefer to form a compound of cyanogen with ammonia or with analkali metal or with hydrogen, as less energy is necessary to form thecyanogen compounds and a lower temperature may be used in the apparatus.

Inasmuch as the invention of this application for patent relates to theprocess, it is independent of the particular means or ap paratusemployed, but for the purpose of a clear and definite description of myinvention I have chosen to describe it in connection with an apparatusof a character suitable for the practice of said invention or process.

In the drawings, Figurel is a section of said apparatus on the line 1-4of Fig. 2; Fig. 2 a cross-section taken through the retort on the line22. of Fig. 1 but'on a larger scale; and Fig. 3 a section on the line3-3 of Fig. 1 on a reduced scale.

A rotary drum A is supported upon standards L L by means of hollowtrunnions S S extending from opposite ends of the drum. These trunnionscommunicate with the interior of the drum and the trunnion S is flangedbeyond the standard L and coupled toa supply pipe D by means of acoupling plate J attached to the flange of the supply pipe.- The hollowtrunnion S. is secured to a perforated conduit or tube S which forms therotary support for hollow vanes K which, revolve within the absorber H.The drum A is provided with a refractory lining I within the metal shellM and an electric resistor R of carbon or. other suitable materialextends from end to end of the drum and is connected by'means ofconductors W and IV at the opposite ends of the drum with exteriorannular con'- ductors W and which are in turn en-' gaged by brushes Wand W which supply the current for heating the interior of the drum.-

At 0 is shown a manholefor giving access to the interior of the drum forcharging, cleaning, etc. Rotation is imparted to the drum by means of aband wheel or pulley S upon the hollow trunnion-S and communicationbetween the hollow trunnion and the perforated tube section S iscontrolled by a valve V having a valve stem -V the outer end of whichbears a grooved head V engaged by a hand lever V for operating thevalve.

At 8 are shown perforations by which the tube section S communicateswith the interiors of the hollow vanes K and the lat ter are in'turnprovided with apertures is by which the gas may pass" to the interior ofthe absorbing chamber H and to the liquid contained therein. I

At 0 I have indicated an outlet by which the liquid may be withdrawnwhen suitably ,impregnated,'at X is shown an exhaust for the unabsorbedgases and at Z a manhole for securing access to'the interior of theabsorber. I

VVhile' I have described with some particularity the apparatus by whichmy process is carried out, it will be understood that itis not a part ofthe present invention which may be readily carried out in a greatvariety of other apparatus.

In practice I prefer to place in the drum A a metal which is capable ofuniting with nitrogen to form a nitrid, such as an alkaline earth metal,magnesium or calcium, though other metals, such as iron, zinc oraluminum, may also be-used. When metallic magnesium is placed in theretortand heated to a temperature of 400=to 500 C. and nitrogen isintroduced through the shaft S and the retort revolved, an intimatecontact takes place between the heated magnesiumand the nitrogen, thereaction being V e+ fgi i If charcoal or other forms of carbon areplaced in the retort in contact with-the magnesium nitrid, and hydrogenH and ammonia NH is introduced through the shaft S and the retortrevolved and suitable current passed through the resistance R so thatthe temperature in the retort is raised to a point between 300 and 600(1., a reaction will take place in which the carbon will unite with thenitrogen of the magnesium nitrid to form cyanogen, and this will reactwith the hydrogenand ammonia forming ammonium cyanid N I-LCN andhydrocyanic acid HON. The ammonium cyanid is readily decomposed intohydrocyanic acid HCN and ammonia NH at temperatures in excess of 35 to40 0., so that'the pro ortions of the ammonium cyanid and of hy rocyanicacid will depend upon the amount of gases introduced and thetemperatures at which they are discharged into the absorber .-B. In thisabsorber I preferably place a mixture of sodium chlorid NaCl and aqueousammonia NH aq. The reactions in the retort will then takeplace inaccordance with the equation also a secondar reaction may take place asfollows NILCNZNH, HUN.

and in the case of the hydrocyanic acid the reaction will take place inaccordance with the equation NaCl N11 HON 2N aCN Nil-I 01.

. It will be apparent in the above reactions that the absorber maycontain only an aqueous solution of sodium chlorid or it may contain asolution of sodium chlorid and aqua ammonia. The ammonia for decomposingthe sodium chlorid may be transferred from the-retort t0 the absorber bymeans of the ammonium cyanid or by means of the hydrocyanic acid andammonia, or ammonia may be added direct to the solution in absorbe Itwill of course be obe'ious to anyone familiar. with chemistry that it isimmaterial whether ammonia and hydrocyanic acid or ammonium cyanidenterthc absorber and in fact as appears above a mixtureof all thesesubstances will normally be formedand pass into the absorber. Thereforein the claims devbted to this i'cature'of the invention I have referredonly tothe mixture of hydrocyanic acid and ammonia but it will beunderstood that sodium chlorid be in the proportions necessary toentirely react, as In practice an excess of sodium chloridmay be used.The contents of the absorber may be removed by means of the exit pipe Cand fresh solutioninserted. As sodium chlorid is not readily soluble ina solution of ammonium chlorid,

the excess of sodium'chlorid is readily precipitated and the solution ofsodiumicyanid and ammonium chlorid may be removed from the absorber andsubsequently'treated for the. recovery of the various compounds. In theabove reactions it will be noted 'that the metallic magnesium isrecoveredand, hence, can again be used for the fixation of a furtheramount of atmospheric nitrogen. It will also be apparent that otherchemicals may be placed 111 the retort or other solutions used in theabsorber. If metallic sodium Na and charcoal or carbon C be placed inthe retorttogether with ma nesium nitrid Mg,N and ammonia N 3 be passedthrough the shaft S, at a tempera.-

ture from 200. to 300 0., the ammonia and sodium readily reducethemagnesium n'itrid,

and sodium cyanid is formed in the retort and may be removed through theopening and manhead C. Anyexcess of ammonia and hydrogen will then passinto the absorber and the excess of ammonia may be recovered. In thisreaction a higher =tem- '6 perature may be maintained in the retort ifdesired, and the ammonia may be inserted 1n a compressed or liquefiedform and if desired, the'temperature may be regulated by this liquefiedammonia. The reaction when using metallic sodium and ammonia will be Ihave discovered that in all the reactions in the retort where nitrogenis caused to react, the presence'of metallic magnesium Mg exercisesavery beneficial effect. Ordinarily the nitrogen readily escapes in thereactions where ammonia is decomposed or is caused to react, but withthe'presenee of metallic magnesium, owing to the ability of the metallicmagnesium, wheirthe temperature is slightly raised to act with nitrogen,the nitrogen is caused to more readily react by the presence of themetallic magnesium. In the ordinary formation of cyanogen (LN the heatof formation is a negative value approximating 65 calories. The heat offormation inthe presence of hydrogen forming hydrocyanic acid has a lessnegative value. The heat of formation to form a cyanid either withammonia or with an alkali such as potassium or sodium possesses apositive value of from 5 to30 calories. It is, therefore, possible toform ammonia cyanid, a

metal cyanid, or to form hydrocyanic acid with less energy than isrequired in the formation of the cyanogen radical alone.

In the above reactions I prefer to unite the' cyanogen radical with ametal or its Zequiva'lent such as hydrogen, ammonia or gases or fromother sources, with or with out concentration or purification and boththe nitrogen and-ammonia may be inserted in a gaseous form or in aliquid form and the temperature of the-retort may be altered by thecombined action of the resistance R and that due to the cooling actionof the eX- pansion of liquid ammonia or nitrogen. It will also beapparent that -ammonlum 'cy anid may be formed dlrectly from ammonia andcarbon or from ammonia, hydrogen and character.

carbon by simply heating carbon in the retort to a temperature of 1,000-C. to 1,100 C. and passing ammonia or a mixture of ammonia and hydrogenthrough the pipcfi and causing an intimate mixture with the highlyheated carbon, or the alkaline earth metals may be reduced directlyfromtheir salts in the presence of the highly heated carbon and nitrogenor' ammonia caused to react with them. These reactions require atemperature of 1,400 C. to 1,500 C., Whereas the reactions with metalscapable of forming nitrids from nitrogen or ammonia. take place at from300 C. to 600 C. depending -on the metals used. Magnesium forming anitrid with nitrogen at about .00 C. while iron forms a nitrid withammonia at. about 700 C.

In all reactions involving the formation of ammonium cyanid orhydrocyanic acid it is desirable to absorb the gases effectively onaccount of their extremely poisonous Various salt solutions may be usedto absorb the gases, forming a cyanid of a metal when decomposed by thegases from the retort.

In certain of the following claims I have used the word metal to includenot only elements commonly classified as such but also the elementhydrogen, which, though not always classified as a metal, is recognizedto possess many of the properties thereof and under the circumstancesdoscribed acts as such. It will be obvious that the metal and carbonwhich.I employ need not be in the elemental state, for it may be ofheated carbonaceous material and ametal.

4. The process of preparing nitrogenous compounds which comprisestreating a metal nitrid with ammonia and hydrogen in the presence ofheated carbonaceous .material. a

5. {The process of preparing nitrogenous compounds which comprisestreating an alkaline earth metal nit-rid with hydrogen and ammonia incontact with heated carbonaceous material. 5

6. The process of preparing nitrogenous compounds which comprisestreating a nitrid of magnesium with ammonia and hydrogen in contact withheated carbonaceous material. r

7. The process of preparing nitrogenous compounds which consists intreating an alkali earth metal with nitrogen to form a nitrid andtreating the nitrid with carbonaceous material and ammonia to form acyanid and restoring the metal to a condition capable of again unitingwith nitrogen.

8. The process of preparing nitrogenous compounds which consists intreating magnesium with nitrogen to form a nitrid'and treating themagnesium nitrid with car- LELAND L. SUMMERS.

Witnesses:

' S. E. HIBBEN, g LOUIS B. ERWIN.

Copies of this patent may be obtained-for five cents each, by addressingthe Commissioner of Patents, Washington, D. 0.

